1. Field of the Invention
The present invention relates, in general, to a magnetron for microwave ovens and, more particularly, to an anode of a magnetron for microwave ovens, which allows the magnetron to have an optimal performance while causing a manufacturing process of the anode to be simplified and assembly of the anode to be easily performed.
2. Description of the Related Art
Generally, a magnetron for microwave ovens is a high frequency oscillation tube having a fundamental frequency at 2450 MHz. The magnetron includes a cathode and an anode coaxially arranged to form an electric field, and a pair of pole pieces to form magnetic fields above and below the cathode and the anode.
A structure of an anode 100 is described in detail below. As shown in FIG. 1, the anode 100 includes an anode cylinder 110, a plurality of vanes 120 radially arranged in the anode cylinder 110 to form a resonant cavity, a plurality of strap rings 130 to electrically connect the plurality of vanes 120 to each other, and an antenna 140 connected to one of the plurality of vanes 120 to radiate microwaves. Assembly accuracy of the above-described component parts greatly influences performance of a magnetron. The anode 100 of the magnetron is manufactured by a conventional manufacturing method described below.
The anode cylinder 110, the plurality of vanes 120, the strap rings 130, and the antenna 140 are separately formed. The anode cylinder 110 is formed by cutting off and processing a pipe-shaped material, strap ring notches 121 are formed in each of the vanes 120 to fasten the strap rings 130, and an antenna notch 122 is formed in one of the plurality of vanes 120 to fasten the antenna 140.
Further, the strap rings 130 and the antenna 140 are brazed with a brazing material to be joined to the vanes 120.
The component parts are mounted on an assembly jig. The anode cylinder 110, the plurality of vanes 120, the strap rings 130, and the antenna 140 are fastened at predetermined locations using the assembly jig. A wire shaped brazing material is supplied from predetermined locations so that the wire shaped brazing material inserts between the plurality of vanes 120 and the anode cylinder 110.
The assembly jig on which the component parts are fastened is placed into a brazing furnace and is heated to more than 800° C. so that the brazing material melts and the component parts are joined to each other.
However, the conventional method of manufacturing the anode 100 of the magnetron is problematic in that complicated brazing processes, in which the wire shaped brazing material is used and the strap rings 130 and the antenna 140 must be separately plated with the brazing material, must be performed to braze the component parts. Furthermore, when the wire shaped brazing material is insufficiently inserted into joint portions, a brazing defect may be incurred.